#include <stdio.h>

/*出售金鱼*/

void main()
{
    int i,j,n=0,x;
    for(i=23;n==0;i+=2)
    {
        for(j=1,x=i;j<=4&&x>=11;j++)
        if((x+1)%(j+1)==0)
        x-=(x+1)/(j+1);
        else {x=0;break;}
        if(j==5&&x==11)
        {
            printf("There are %d fishes at first.\n",i);
            n=1;
        }
    }
}
